Debt Obligations (Maturities) (Details) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Future expected/scheduled maturities of outstanding debt and capital lease | ||
| 2018 (remaining nine months) | $ 148,260 | |
| 2019 | 618,679 | |
| 2020 | 672,695 | |
| 2021 | 686,225 | |
| 2022 | 500,000 | |
| Thereafter | 3,025,453 | |
| Total debt maturities | 5,651,312 | |
| Net unamortized premiums and discounts | 884 | |
| Net unamortized debt issuance costs | (30,085) | |
| Total debt obligations, net | $ 5,622,111 | $ 5,676,238 |